The background of the invention will be discussed in two parts.
1. Field of the Invention
This invention relates to spacers, and more particularly to spacers for use in installing ceramic or clay tile on a floor or the like.
2. Description of the Prior Art
Ceramic or clay tile is installed, usually on prepared surface, such as concrete flooring, or other prepared floor or wall surfaces, by first applying a layer of suitable adhesive material, usually a concrete based adhesive. The tiles are normally square, but my be rectangular in form, and of a thickness between one-eighth and three-eighths of an inch. With reference to an alignment mark, such as a blue chalk line, a straightedge, a level or the like, the tile is then placed in position in a row with spacers at the junction of two or more tiles.
Such spacers are normally formed of a plastic material with a relatively high amount of flexure and are used for aligning and spacing tiles relative to each other on the supporting surface. The spacers are normally cross-shaped or cruciform in plan view, that is, in the nature of a "+" symbol. When tiles are placed next to a wall or the like, one leg of the spacer may be cut off with scissors or snips to create a "T" configuration. When the tiles are arranged in a matrix, such as a checkerboard pattern, a cruciform spacer is placed at the junction of the four adjacent corners of four adjacent tiles, or in the case of a wall area, a T-shaped spacer is used.
The use of the spacers performs two functions. In the first place, the spacers provide a uniform or consistent spacing between the tiles, thus providing a geometrically correct appearance. The second function, with respect to four adjacent tiles, is alignment, that is, to assist in maintaining the corners correct, such that the tiles will be oriented properly relative to one another with respect to the mutually perpendicular spacing requirements.
After the base, or adhesive coat sets, the spacers are then removed. This is not done in all cases, but is especially important when the tile is thinner, and there is a small difference between the height of the spacer and the thickness of the tile. Spacers in current use are about three-sixteenths of an inch, or slightly more, in thickness. The width of the individual legs determines the spacing between tiles, and may typically be three-sixteenths of an inch to one-fourth of an inch, or sometimes up to five-eighths of an inch or more.
In any event, some form of tool is normally employed to remove the spacers, such as a small pry bar or a screwdriver or the like. The removal of the spacers is complicated by two things, one being that with the relatively flat bottom surface, the spacer adheres to the adhesive.
Secondly, with the flexible nature of the spacers, and, depending on the skill of the installer, there is a likelihood that adjacent tiles will be in frictional abutting relation with the spacer essentially wedged in between the tiles. In such instances, when an attempt is made to remove the spacers, there is resistance. With the use of metal tools, such as a screwdriver, to assist in the removal, there is another problem, which relates to the high probability of chipping the edges of the tiles during such removal, that may readily occur with ceramic tiles. When tiles are chipped, the installer has a problem of either replacing the chipped tiles, or risking the wrath of the owner for a non-workmanlike job. In either event, there is time and expense involved. The final step in the process is to install grout in the space between the tiles.
If the spacers are left in place when the grout is installed, the area which includes the spacer will have less grout than the surrounding spaces due to the thickness of the spacer. With less grout, and with the resilience of the spacer, the likelihood exits of cracking of the grout at these locations. In addition, when grout is applied it has a consistency which enables it to fill voids, that is, it can flow. In addition, a squeegee or trowel is used to apply some pressure to the grout when filling the spaces, to force it into the voids. The spacers are located at the corners of the tile, and, if there is any space at the lower surface where it contacts the adhesive, there is an additional risk of cracking of the tile at the corners on failure to remove the spacers.
A conventional spacer for use with tile is shown and described in U.S. Pat. No. 2,031,684, entitled "Tile Spacer", which issued to Berger on Feb. 25, 1936.
Another tile spacer for enabling the removal thereof after tile installation is shown and described in U.S. Pat. No. 2,930,135, entitled "Tile Setting Gauge", which issued to Rodtz, Sr. on Mar. 29, 1960. In this spacer member, the spacer is generally cross-shaped or T-shaped and, in one embodiment, has a uniform height throughout, which height is about twice that of the the tile to provide a handle for removal of the spacer. The flooring contacting portion is provided with depending ends, referred to as edge-like bearing points, which are intended to hold the lower surface of the spacer elevated above the adhesive covered supporting surface. In a second embodiment, the two, three and four arms of the spacer in contact with the supporting surface are of a lesser height with a wing shaped projection providing a gripping handle for removal. In all of the embodiments, the vertical sides are parallel to one another, that is, the arms which intrude into the space between tiles are of uniform cross-section. As a result, if the tiles are placed in close abutting relation in the corner spaces, there is a high degree of friction which provides resistance to withdrawl of the spacers. Furthermore, with the configuration of the spacers an inordinate amount of material is required for each spacer.
Another spacer for use with tile is shown and described in U.S. Pat. No. 4,503,654, entitled "Method and Apparatus for Laying Tile", which patent issued to Cosentino on Mar. 12, 1985, this device being constructed as a non-removable spacer.
Other patents which show spacing or aligning type devices for concrete block or glass building blocks are: U.S. Pat. No. 2,797,495, entitled "Glass Building Block Aligner", which issued to Walston on July 2, 1957; and U.S. Pat. No. 4,408,398, entitled "Gauge for Laying Blocks", which issued to Glaze on Oct. 11, 1983.
In accordance with an aspect of the present invention, it is an object to provide a new and improved economical spacer for tile laying which enables the ready removal thereof.